Adding ability to override allocatable resources via ASG tags.

cluster-autoscaler/cloudprovider/aws/aws_manager.go

@@ -247,6 +247,11 @@ func (m *AwsManager) buildNodeFromTemplate(asg *asg, template *asgTemplate) (*ap
 	node.Status.Capacity[gpu.ResourceNvidiaGPU] = *resource.NewQuantity(template.InstanceType.GPU, resource.DecimalSI)
 	node.Status.Capacity[apiv1.ResourceMemory] = *resource.NewQuantity(template.InstanceType.MemoryMb*1024*1024, resource.DecimalSI)
 
+	resourcesFromTags := extractAllocatableResourcesFromAsg(template.Tags)
+	if val, ok := resourcesFromTags["ephemeral-storage"]; ok {
+		node.Status.Capacity[apiv1.ResourceEphemeralStorage] = *val
+	}
+
 	// TODO: use proper allocatable!!
 	node.Status.Allocatable = node.Status.Capacity
 
@@ -293,6 +298,28 @@ func extractLabelsFromAsg(tags []*autoscaling.TagDescription) map[string]string
 	return result
 }
 
+func extractAllocatableResourcesFromAsg(tags []*autoscaling.TagDescription) map[string]*resource.Quantity {
+	result := make(map[string]*resource.Quantity)
+
+	for _, tag := range tags {
+		k := *tag.Key
+		v := *tag.Value
+		splits := strings.Split(k, "k8s.io/cluster-autoscaler/node-template/resources/")
+		if len(splits) > 1 {
+			label := splits[1]
+			if label != "" {
+				quantity, err := resource.ParseQuantity(v)
+				if err != nil {
+					continue
+				}
+				result[label] = &quantity
+			}
+		}
+	}
+
+	return result
+}
+
 func extractTaintsFromAsg(tags []*autoscaling.TagDescription) []apiv1.Taint {
 	taints := make([]apiv1.Taint, 0)
 

cluster-autoscaler/cloudprovider/aws/aws_manager_test.go

@@ -33,6 +33,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/mock"
 	apiv1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
 	"k8s.io/autoscaler/cluster-autoscaler/cloudprovider"
 	kubeletapis "k8s.io/kubernetes/pkg/kubelet/apis"
 )
@@ -82,6 +83,31 @@ func TestBuildGenericLabels(t *testing.T) {
 	assert.Equal(t, cloudprovider.DefaultOS, labels[kubeletapis.LabelOS])
 }
 
+func TestExtractAllocatableResourcesFromAsg(t *testing.T) {
+	tags := []*autoscaling.TagDescription{
+		{
+			Key:   aws.String("k8s.io/cluster-autoscaler/node-template/resources/cpu"),
+			Value: aws.String("100m"),
+		},
+		{
+			Key:   aws.String("k8s.io/cluster-autoscaler/node-template/resources/memory"),
+			Value: aws.String("100M"),
+		},
+		{
+			Key:   aws.String("k8s.io/cluster-autoscaler/node-template/resources/ephemeral-storage"),
+			Value: aws.String("20G"),
+		},
+	}
+
+	labels := extractAllocatableResourcesFromAsg(tags)
+
+	assert.Equal(t, resource.NewMilliQuantity(100, resource.DecimalSI).String(), labels["cpu"].String())
+	expectedMemory := resource.MustParse("100M")
+	assert.Equal(t, (&expectedMemory).String(), labels["memory"].String())
+	expectedEphemeralStorage := resource.MustParse("20G")
+	assert.Equal(t, (&expectedEphemeralStorage).String(), labels["ephemeral-storage"].String())
+}
+
 func TestExtractLabelsFromAsg(t *testing.T) {
 	tags := []*autoscaling.TagDescription{
 		{